According to Gawker, your own SFS editor interviewed Common the other day and quizzed him on the quick-yet-prominent Zune in his new video and his inclusion in their new Green Room podcast series. Read it. Then discuss.
And, just if you're wondering, he's not the only commercially and artistically successful rapper to be endorsing Microsoft these days. Pharrell is also a PC.
For the record, we're still a Mac, no matter what anyone catches us using at work.